TEMPERATURE DISTRIBUTION IN A SEMI-INFINITE MEDIUM DUE TO A HEAT SORCE OF DIFFERENT SHAPE

Thermographic methods based on IR images are actively used in medical practice for the early diagnosis of diseases, in clinical procedures and surgical operations. One of the weak points of the above methods is that the images are noisy due to the thermal influence of a tissue layer located between a human organ under examination and a thermal imager and they therefore carry only indirectly information about the temperature regime of internal organs. In order to improve the accuracy of remote thermographic methods, as applied to the human skin, the method of temperature estimation due to the presence of heat sources of different origin in the tissue has been developed. This method is based on using the linear systems theory approach and the calculation results of a point source. Sources in the shape of a sphere, a cylinder of different orientation, straight lines, and a circle are considered. Specific features of thermal fields from heat sources are indicated. Simple computational models are obtained for a temperature from a spherical source inside and outside it in an infinite medium. Temperatures from a heated line of finite and infinite length are compared. Using the example of a cylindrical heat source, the temperature inside and outside the source is analyzed in detail as a function of thermal physical parameters, occurrence depth and sizes. Particular attention is paid to comparing the results of the temperature distribution on the surface of the skin and its sizes. The given results can be used for temperature correction in thermographic studies.

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